1. Field of the Invention
The invention relates to a trailer lock and particularly to a trailer lock for locking a trailer ball cap.
2. Description of the Prior Art
Referring to FIG. 1, a conventional camping vehicle 1 and a trailer 2 usually are coupled through a coupling apparatus 3. The coupling apparatus 3 includes a trailer ball 31 on a rear side of the vehicle 1 and a trailer ball cap 32 on one end of the trailer 2. The trailer ball cap 32 can be coupled with the trailer ball 31 to connect the vehicle 1 and the trailer 2 for hauling. However, when the trailer is not coupled with the vehicle, any vehicle equipped with a trailer ball can haul the trailer away. As a result, the trailer is easily stolen. This is an issue troubling many trailer owners.